This invention relates to a method of manufacturing a hollow stabilizer and more particularly to a hollow stabilizer formed of a steel tubing.
Heretofore, a vehicle stabilizer has generally been formed of a solid steel member. In recent years, however, studies have been conducted on the application of a steel tubing in order to reduce the weight of an automobile. A hollow stabilizer has already been put into practice in some quarters. To data, a stabilizer has been prepared from medium carbon steel containing about 0.4 to 0.7 weight % of carbon, or special steel containing a large amount of carbon such as spring steel. Therefore, the material of the conventional stabilizer is expensive. Moreover, the conventional stabilizer has to be subjected to oil quenching by applying costly quenching oil. Further, it has been necessary to provide means for preventing the scattering of oil mist or hot oil and effective fire prevention.
An example of hollow stabilizer is already set forth in the U.S. Pat. Nos. 4,372,576 and 4,378,122. In the case of the hollow stabilizers disclosed in these U.S. Patents and other known hollow stabilizers, it has been the common practice to apply special steel which contains high-carbon, such as spring steel. Moreover, oil quenching has generally been applied in heat-treatment of the conventional stabilizer, thereby presenting the aforementioned problems.